U.S. patent number 11,207,992 [Application Number 16/121,056] was granted by the patent office on 2021-12-28 for power conversion system for vehicles and control method thereof.
This patent grant is currently assigned to Hyundai Motor Company, Kia Motors Corporation. The grantee listed for this patent is Hyundai Motor Company, Kia Motors Corporation. Invention is credited to Jong Pil Kim, Dae Woo Lee, Woo Young Lee, Youn Sik Lee, Jin Myeong Yang, In Yong Yeo.
United States Patent |
11,207,992 |
Yeo , et al. |
December 28, 2021 |
Power conversion system for vehicles and control method thereof
Abstract
A power conversion system for vehicles is provided. The system
includes a switching circuit having first input/output terminals,
second input/output terminals and a plurality of switching elements
connected between the first input/output terminals and the second
input/output terminals. A first energy storage device is connected
to the second input/output terminals and has a preset
charging/discharging voltage. A first voltage conversion circuit
converts power output from the first input/output terminals to
output a voltage less than the voltage of the first energy storage
device. A second energy storage device is charged/discharged with
the output voltage of the first voltage conversion circuit. A
controller controls open/short-circuit states of the switching
elements based on whether the first energy storage device is being
charged and whether the vehicle is traveling. When the first energy
storage device is being charged, AC charging power is provided to
the first input/output terminals from outside of the vehicle.
Inventors: |
Yeo; In Yong (Gyeonggi-do,
KR), Yang; Jin Myeong (Gyeonggi-do, KR),
Lee; Woo Young (Gyeonggi-do, KR), Lee; Youn Sik
(Gyeonggi-do, KR), Lee; Dae Woo (Incheon,
KR), Kim; Jong Pil (Do, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
Hyundai Motor Company
Kia Motors Corporation |
Seoul
Seoul |
N/A
N/A |
KR
KR |
|
|
Assignee: |
Hyundai Motor Company (Seoul,
KR)
Kia Motors Corporation (Seoul, KR)
|
Family
ID: |
1000006017855 |
Appl.
No.: |
16/121,056 |
Filed: |
September 4, 2018 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20190315233 A1 |
Oct 17, 2019 |
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Foreign Application Priority Data
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Apr 17, 2018 [KR] |
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10-2018-0044634 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60L
53/20 (20190201); B60L 50/66 (20190201); B60L
2210/30 (20130101); B60L 2210/22 (20130101) |
Current International
Class: |
B60L
53/20 (20190101); B60L 50/60 (20190101) |
Field of
Search: |
;307/9.1-10.8
;320/103-104 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2013-0117210 |
|
Oct 2013 |
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KR |
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10-1489226 |
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Feb 2015 |
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KR |
|
10-1558794 |
|
Oct 2015 |
|
KR |
|
2017-0131895 |
|
Dec 2017 |
|
KR |
|
Primary Examiner: Barnie; Rexford N
Assistant Examiner: Willoughby; Terrence R
Attorney, Agent or Firm: Mintz Levin Cohn Ferris Glovsky and
Popeo, P.C. Corless; Peter F.
Claims
What is claimed is:
1. A power conversion system for vehicles included in a vehicle,
comprising: a switching circuit including first input/output
terminals, second input/output terminals, and a plurality of
switching elements connected between the first input/output
terminals and the second input/output terminals, wherein the
switching circuit is a bi-directional alternating current/direct
current (AC/DC) converter; a first energy storage device connected
to the second input/output terminals and having a preset
charging/discharging voltage; a first voltage conversion circuit
for converting power output from the first input/output terminals
to output a voltage less than the voltage of the first energy
storage device; a second energy storage device charged/discharged
with the output voltage of the first voltage conversion circuit;
and a controller configured to control open/short-circuit states of
the plurality of switching elements based on whether the first
energy storage device is being charged and whether the vehicle is
being driven, wherein when the first energy storage device is being
charged, then alternating current (AC) charging power for charging
the first energy storage device is provided to the first
input/output terminals from outside of the vehicle, and wherein the
first input/output terminals are connected to a charging port to
receive the AC charging power from the outside.
2. The power conversion system for vehicles according to claim 1,
further comprising: a switching unit configured to determine an
electrical connection state between the first input/output
terminals and the first voltage conversion circuit.
3. The power conversion system for vehicles according to claim 2,
wherein the controller is configured to open the switching unit and
operate the plurality of switching elements to convert the AC
charging power provided to the first input/output terminals to
output the charging/discharging voltage of the first energy storage
device through the second input/output terminals when the first
energy device is being charged.
4. The power conversion system for vehicles according to claim 2,
wherein the controller is configured to short-circuit the switching
unit and control the plurality of switching elements to convert the
power of the first energy storage device provided to the second
input/output terminals into AC power to be output through the first
input/output terminals when the vehicle is being driven.
5. The power conversion system for vehicles according to claim 4,
wherein the first voltage conversion circuit is configured to
convert the AC power of the first energy storage device provided
from the first input/output terminals to output a direct current
(DC) voltage less than the voltage of the first energy storage
device.
6. The power conversion system for vehicles according to claim 1,
wherein the switching circuit is a full-bridge circuit including
the plurality of switching elements.
7. The power conversion system for vehicles according to claim 1,
wherein the first voltage conversion circuit includes: a
transformer configured to change the level of AC power provided
from the first input/output terminals; and a rectifier configured
to rectify an AC voltage output from the transformer to output a
direct current (DC) voltage.
8. The power conversion system for vehicles according to claim 1,
further comprising: a second voltage conversion circuit configured
to receive a direct current (DC) voltage of the first energy
storage device and convert the DC voltage into a power supply
voltage of an electrical load of the vehicle.
9. The power conversion system for vehicles according to claim 8,
wherein the controller is configured to operate the second voltage
conversion circuit when the first energy storage device is being
charged.
10. A method of controlling a power conversion system of claim 1,
comprising: determining, by a controller, whether the first energy
storage device within the vehicle is being charged and whether the
vehicle being driven; opening, by the controller, a switching unit
which is configured to determine an electrical connection state
between the first input/output terminals and the first voltage
conversion circuit and operating the plurality of switching
elements to convert alternating current (AC) charging power
provided to the first input/output terminals to output a
charging/discharging voltage of the first energy storage device
through the second input/output terminals in response to
determining that the first energy device is being charged; and
short-circuiting, by the controller, the switching unit and
operating the plurality of switching elements to convert power of
the first energy storage device provided to the second input/output
terminals into AC power to be output through the first input/output
terminals in response to determining that the vehicle is being
driven.
11. The method of controlling a power conversion system for
vehicles according to claim 10, further comprising: operating, by
the controller, a second voltage conversion circuit, which is
configured to receive a direct current (DC) voltage of the first
energy storage device and convert the DC voltage into a power
supply voltage of an electrical load of the vehicle in response to
determining that the first energy storage device is being charged.
Description
CROSS REFERENCE TO RELATED APPLICATION
The present application claims priority to Korean Patent
Application No. 10-2018-0044634, filed Apr. 17, 2018, the entire
contents of which is incorporated herein for all purposes by this
reference.
BACKGROUND
1. Field of the Invention
The present invention relates to a power conversion system for
vehicles and a control method thereof, and more particularly, to a
power conversion system which improves space utilization by
decreasing the size of the power conversion system.
2. Description of the Related Art
In general, battery charging methods of environmentally friendly
vehicles may be divided into a slow charging method and a quick
charging method. Specifically, the slow charging method refers to a
method of applying an external alternating current (AC) voltage for
home use or general buildings to an on-board charger (OBC) mounted
within a vehicle through a charging stand (e.g., external charger)
or the like to rectify the AC voltage into a direct current (DC)
voltage, boosting the DC voltage to a DC voltage suitable for
charging and then charging a high voltage battery with the DC
voltage. The quick charging method refers to a method of outputting
high current to perform charging within a shorter period of time
than the time required for slow charging. Since the quick charging
method requires more than ten times the rated power of slow
charging, a quicker charger is unable to be mounted within a
vehicle and thus, a dedicated quick charger is required to be
installed separately.
Meanwhile, an on-board charger for rectifying an external AC
voltage into a DC voltage, as described above, is required to be
mounted in environmentally friendly vehicles chargeable through the
slow charging method. To improve availability of a limited space
within a vehicle, research is being actively conducted regarding
reducing the sizes of power elements and devices mounted within a
vehicle including the on-board charger.
SUMMARY
The present invention provides a power conversion system for
vehicles and a control method thereof which improves space
utilization and reduces costs by decreasing the size of the power
conversion system by using a plurality of switching elements in a
switching circuit and a first voltage circuit.
To accomplish the object, a power conversion system for vehicles
according to the present invention may include: a switching circuit
having first input/output terminals, second input/output terminals
and a plurality of switching elements connected between the first
input/output terminals and the second input/output terminals; a
first energy storage device connected to the second input/output
terminals and having a preset charging/discharging voltage; a first
voltage conversion circuit for converting power output from the
first input/output terminals to output a voltage less than the
voltage of the first energy storage device; a second energy storage
device charged/discharged to the output voltage of the first
voltage conversion circuit; and a controller configured to operate
open/short-circuit states of the plurality of switching elements
based on whether the first energy storage device is being charged
and whether the vehicle is traveling. Additionally, AC charging
power for charging the first energy storage device may be provided
to the first input/output terminals from outside of the vehicle
when the first energy storage device is being charged.
The power conversion system for vehicles may further include a
switching unit configured to determine an electrical connection
state between the first input/output terminals and the first
voltage conversion circuit. The controller may be configured to
open the switching unit and operate the plurality of switching
elements to convert the AC charging power provided to the first
input/output terminals to thus output the charging/discharging
voltage of the first energy storage device through the second
input/output terminals when the first energy device is being
charged.
The controller may be configured to short-circuit the switching
unit and operate the plurality of switching elements to convert the
power of the first energy storage device provided to the second
input/output terminals into AC power to be output through the first
input/output terminals when the vehicle is traveling. The first
voltage conversion circuit may be configured to convert AC power of
the first energy storage device provided from the first
input/output terminals to output a DC voltage less than the voltage
of the first energy storage device.
The switching circuit may be a full-bridge circuit including the
plurality of switching elements. The first voltage conversion
circuit may include: a transformer configured to change the level
of an AC power provided from the first input/output terminals; and
a rectifier configured to rectify an AC voltage output from the
transformer to output a DC voltage. The power conversion system for
vehicles may further include a second voltage conversion circuit
configured to receive a DC voltage of the first energy storage
device and convert the DC voltage into a power supply voltage of an
electrical load of the vehicle. The controller may then be
configured to drive the second voltage conversion circuit when the
first energy storage device is being charged.
To accomplish the object, a method of controlling a power
conversion system for vehicles according to the present invention
may include: determining whether a first energy storage device
within a vehicle is being charged and whether the vehicle is
traveling; opening a switching unit and operating a plurality of
switching elements to convert AC charging power provided to first
input/output terminals to output a charging/discharging voltage of
the first energy storage device through second input/output
terminals upon determining that the first energy device is being
charged; and short-circuiting the switching unit and operating the
plurality of switching elements to convert power of the first
energy storage device provided to the second input/output terminals
into AC power to be output through the first input/output terminals
upon determining that the vehicle is traveling. The method may
further include driving second voltage conversion circuit upon
determining that the first energy storage device is being
charged.
According to the present invention, it may be possible to decrease
the size of the power conversion system by using the plurality of
switching elements in the switching circuit and the first voltage
circuit, thereby improving space utilization and reducing
costs.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and other advantages of the
present invention will be more clearly understood from the
following detailed description taken in conjunction with the
accompanying drawings, in which:
FIG. 1 is a schematic diagram showing a configuration of a power
conversion system for vehicles according to an exemplary embodiment
of the present invention;
FIG. 2 is a detailed diagram showing the power conversion system
for vehicles according to an exemplary embodiment of the present
invention;
FIG. 3 is a diagram showing a flow of power provided from outside
when a first energy storage device is charged in the power
conversion system for vehicles according to an exemplary embodiment
of the present invention;
FIG. 4 is a diagram showing a flow of power provided from the first
energy storage device when a vehicle is traveling in the power
conversion system for vehicles according to an exemplary embodiment
of the present invention; and
FIG. 5 is a flowchart of a method of controlling the power
conversion system for vehicles according to an exemplary embodiment
of the present invention.
DETAILED DESCRIPTION
It is understood that the term "vehicle" or "vehicular" or other
similar term as used herein is inclusive of motor vehicles in
general such as passenger automobiles including sports utility
vehicles (SUV), buses, trucks, various commercial vehicles,
watercraft including a variety of boats and ships, aircraft, and
the like, and includes hybrid vehicles, electric vehicles, plug-in
hybrid electric vehicles, hydrogen-powered vehicles and other
alternative fuel vehicles (e.g. fuels derived from resources other
than petroleum). As referred to herein, a hybrid vehicle is a
vehicle that has two or more sources of power, for example both
gasoline-powered and electric-powered vehicles.
Although exemplary embodiment is described as using a plurality of
units to perform the exemplary process, it is understood that the
exemplary processes may also be performed by one or plurality of
modules. Additionally, it is understood that the term
controller/control unit refers to a hardware device that includes a
memory and a processor. The memory is configured to store the
modules and the processor is specifically configured to execute
said modules to perform one or more processes which are described
further below.
Furthermore, control logic of the present invention may be embodied
as non-transitory computer readable media on a computer readable
medium containing executable program instructions executed by a
processor, controller/control unit or the like. Examples of the
computer readable mediums include, but are not limited to, ROM,
RAM, compact disc (CD)-ROMs, magnetic tapes, floppy disks, flash
drives, smart cards and optical data storage devices. The computer
readable recording medium can also be distributed in network
coupled computer systems so that the computer readable media is
stored and executed in a distributed fashion, e.g., by a telematics
server or a Controller Area Network (CAN).
The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the invention. As used herein, the singular forms "a", "an" and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. It will be further understood
that the terms "comprises" and/or "comprising," when used in this
specification, specify the presence of stated features, integers,
steps, operations, elements, and/or components, but do not preclude
the presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof. As
used herein, the term "and/or" includes any and all combinations of
one or more of the associated listed items.
Unless specifically stated or obvious from context, as used herein,
the term "about" is understood as within a range of normal
tolerance in the art, for example within 2 standard deviations of
the mean. "About" can be understood as within 10%, 9%, 8%, 7%, 6%,
5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated
value. Unless otherwise clear from the context, all numerical
values provided herein are modified by the term "about."
Hereinafter, a power conversion system for vehicles and a control
method thereof according to exemplary embodiments of the present
invention will be described with reference to the attached
drawings.
FIG. 1 is a schematic diagram showing a configuration of the power
conversion system for vehicles according to an exemplary embodiment
of the present invention and FIG. 2 is a detailed diagram showing
the power conversion system for vehicles. FIG. 3 is a diagram
showing a flow of power provided from outside when a first energy
storage device is being charged and FIG. 4 is a diagram showing a
flow of power provided from the first energy storage device when a
vehicle is traveling.
Referring to FIGS. 1 to 4, the power conversion system mounted
within a vehicle according to the present invention may include a
switching circuit 100, a first energy storage device 200, a first
voltage conversion circuit 300, a second energy storage device 400,
a controller 600 and a power supply 700. The power conversion
system may further include a switching unit 500 and a second
voltage conversion circuit 800 according to an exemplary
embodiment. A detailed configuration of the power conversion system
according to the present invention will be described in detail
below.
The switching circuit 100 may include first input/output terminals
110, second input/output terminals 120, and a plurality of
switching elements 130 connected between the first input/output
terminals 110 and the second input/output terminals 120. In
particular, the plurality of switching elements 130 connected
between the first input/output terminals 110 and the second
input/output terminals 120 may be connected in a full-bridge
circuit structure and may be configured to convert alternating
current (AC) power into direct current (DC) power or convert DC
power into AC power.
Specifically, the switching circuit 100 may be configured to
convert external AC charging power from the outside (e.g., from an
external charger) through the first input/output terminals 110 from
the power supply 700 into DC power and transfer the DC power to the
first energy storage device 200 connected to the second
input/output terminals 120 such that the first energy storage
device 200 having a preset charging/discharging voltage may be
charged with the DC power. In addition, the switching circuit 100
may be configured to convert DC power input from the first energy
storage device 200 through the second input/output terminals 120
into AC power and output the AC power to the first input/output
terminals 110.
In other words, the switching circuit 100 according to the present
invention may be configured to convert the AC charging power input
from outside through the power supply 700 into DC power and
transfer the DC power to the first energy storage device 200 when
the first energy storage device 200 is being charged and may be
configured to convert DC power input from the first energy storage
device 200 into AC power and transfer the AC power to the second
energy storage device 400 through the first voltage conversion
circuit 300 when the vehicle is traveling.
The first energy storage device 200 may be connected to the second
input/output terminals 120 and may be an energy storage device
having a preset charging/discharging voltage. The first energy
storage device 200 may be a high voltage battery configured to
store and provide electric energy for driving a motor of a vehicle
according to an exemplary embodiment. However, the high voltage
battery is merely an example and various devices capable of storing
and providing electric energy for driving a motor of a vehicle
including a super capacitor may be used as the first energy storage
device of the present invention.
The first voltage conversion circuit 300 may be configured to
convert power output from the first input/output terminals 110 into
a voltage less than the voltage of the first energy storage device
200 and transfer the voltage to the second energy storage device
400. Specifically, the first voltage conversion circuit 300 may be
configured to convert AC power converted from DC power of the first
energy storage device 200 and provided thereto through the first
input/output terminals 110 into a DC voltage less than the voltage
of the first energy storage device 200 and output the DC
voltage.
The first voltage conversion circuit 300 may include a transformer
310 configured to change or adjust the level of an AC voltage
provided from the first input/output terminals 110 and a rectifier
320 configured to rectify the AC voltage output from the
transformer 310 to output a DC voltage. In other words, the first
voltage conversion circuit 300 may be configured to change the
level of the AC power converted from the DC power of the first
energy storage device 200, which is input thereto through the first
input/output terminals 110, through the transformer 310, rectify
the AC voltage output from the transformer 310 into a DC voltage
through the rectifier 320 and transfer the DC voltage to the second
energy storage device 400.
The second energy storage device 400 may be an energy storage
device connected to the output terminal of the first voltage
conversion circuit 300 and charged/discharged with/to the output
voltage of the first voltage conversion circuit 300. The second
energy storage device 400 may be a battery configured to store and
provide electric energy for driving an electrical load 900, a
switched-mode power supply (SMPS) and the like of the vehicle.
However, this is merely exemplary and various devices capable of
storing and providing electric energy for driving the electrical
load 900, the SMPS and the like may be used as the second energy
storage device 400 of the present invention.
The switching unit 500 may be configured to determine an electrical
connection state between the first input/output terminals 110 and
the first voltage conversion circuit 300 and a relay may be used as
the switching unit 500 according to an exemplary embodiment. More
specifically, the switching unit 500 may be open or short-circuited
by the controller 600 as described herein, and thus the first
input/output terminals 110 and the first voltage conversion circuit
300 may be electrically open or short-circuited.
Particularly, the controller 600 may be configured to control
open/short-circuit states of the plurality of switching elements
130 in the switching circuit 100 and open/short-circuit states of
the switching unit 500 based on whether the first energy storage
device 200 is being charged and whether the vehicle is traveling
(e.g., being driven). When the first energy storage device 200 is
being charged, AC power for charging the first energy storage
device 200 may be provided to the first input/output terminals 110
from the outside of the vehicle through the power supply 700, as
shown in FIG. 3. More specifically, the controller 600 may be
configured to open the switching unit 500 and operate the switching
elements 130 in the switching circuit 100 to convert the AC power
provided to the first input/output terminals such that the second
input/output terminals 120 outputs a charging/discharging voltage
of the first energy storage device 200 when the first energy
storage device 200 is being charged.
In addition, the controller 600 may be configured to operate the
second voltage conversion circuit 800 when the first energy storage
device 200 is charged. Particularly, the second voltage conversion
circuit 800 may be a circuit which is provided with the DC voltage
of the first energy storage device 200, may be configured to
convert the DC voltage into a power supply voltage for the
electrical load 900 and the SMPS of the vehicle and provide the
power supply voltage to the electrical load 900 and the SMPS of the
vehicle. In other words, the controller 600 may be configured to
drive or operate the second voltage conversion circuit 800 to
convert the DC voltage provided from the first energy storage
device 200 and supply the converted voltage to the electrical load
900 and the like of the vehicle when the first energy storage
device 200 is being charged.
When the vehicle is being driven, the controller 600 may be
configured to short-circuit the switching unit 500 (e.g., a switch)
and operate the plurality of switching elements 130 to convert the
power of the first energy storage device 200 provided to the first
input/output terminals 120 and output the power as AC power from
the first input/output terminals 110. In other words, the
controller 600 may be configured to operate the plurality of
switching elements 130 to convert the DC power of the first energy
storage device 2100 input to the switching circuit 100 through the
second input/output terminals 120 into AC power to be output
through the first input/output terminals 110 and short-circuit the
switching unit 500 to input the AC power output from the first
input/output terminals 110 to the first voltage conversion circuit
300 and then provide the AC power to the second energy storage
device 400 when the vehicle is being driven.
As described above, the switching circuit and the first voltage
circuit may use the plurality of switching elements in the power
conversion system for vehicles. Accordingly, the size of the power
conversion system may be reduced to improve space utilization and
decrease overall costs.
FIG. 5 is a flowchart of a method of controlling the power
conversion system for vehicles according to an exemplary embodiment
of the present invention. The method described herein below may be
executed by the controller having a processor and a memory. As
shown in FIG. 5, the method of controlling the power conversion
system for vehicles according to an exemplary embodiment of the
present invention may include determining whether the first energy
storage device in a vehicle is being charged and whether the
vehicle is being driven, opening the switching unit and operating
the plurality of switching elements to convert AC charging power
provided to the first input/output terminals to thus output a
charging/discharging voltage of the first energy storage device 200
through the second input/output terminals upon determining that the
first energy device is being charged, and short-circuiting the
switching unit and operating the plurality of switching elements to
convert the power of the first energy storage device provided to
the second input/output terminals into AC power to be output
through the first input/output terminals upon determining that the
vehicle is being driven. In addition, the method may include
driving or operating the second voltage conversion circuit upon
determining that the first energy storage device is being
charged.
Technical features with respect to the steps of the method of
controlling the power conversion system for vehicles according to
the present invention are the same as the above-described features
of the power conversion system for vehicles, and thus detailed
description thereof is omitted.
* * * * *